HIF1A and brain ischemia: Past studies have shown that hypoxia-inducible factor 1-alpha (HIF1α) is an essential protein in Piezo1/calcium signaling, ferritin pendulous regulation, and cerebral ischemia (Guo et al., 2021; Yang et al., 2018), and HIF1α expression is increased in neurons and astrocytes after cerebral ischemia (Hirayama and Koizumi, 2017).